I'm having an odd, and stressing, problem with running a large JUnit Plugin test suite in Eclipse. When I try to re-run a JUnit plugin suite that has just been executed, Eclipse hangs for quite some time before it eventually wakes up and launches. It can take up to 5 minutes sometimes, and increases with the size of the suite. Visually, it appears as a GC cleanup, except that I have plenty of GC space available (400 MB freely allocated).

The size of the workspace that is has to delete is well under 1 GB, and there are not too many files - definitely less than 20,000.

While I was waiting for a new run to start, I decided to manually kill explorer.exe to see if it had any effect. Surprisingly, Eclipse instantly fell out of its freeze and ran as normal.

This makes me think that Windows is somehow interfering with the deletion of these workspace files. They're not being put into the Recycle Bin though. The workspace is in C: which I think is out of the range of any workspace/domain stuff. Any ideas?